The present disclosure generally relates to semiconductor structures, and particularly to a gate electrode including a material stack configured for scavenging oxygen and method of manufacturing the same.
Dielectric metal oxides having a dielectric constant greater than 7.9 (which is the dielectric constant of silicon nitride) are employed as a gate dielectric material for advanced field effect transistors. Interfacial oxide layers are collaterally formed at interfaces between a dielectric metal oxide material in a gate dielectric and other materials such as the semiconductor material of the channel and the conductive material of the gate electrode. The interfacial oxide layers reduce the effective dielectric constant of the gate dielectric, and therefore, the thickness of the interfacial oxide layers need to be minimized in order to provide high performance field effect transistors.